Pinecone
En-Route
Because G100UL is not "aviation gasoline" as it does not meet ASTM D910.
Which is why you need an STC for MOGAS, even though it is higher octane than the 73 you require.
GAMI G100UL STC available now
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Because G100UL is not "aviation gasoline" as it does not meet ASTM D910.
Which is why you need an STC for MOGAS, even though it is higher octane than the 73 you require.
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Bro do you even lift
wonder if there will be a firesale on 100ll when this stuff comes out, peeps trying to clear their tanks and whatnot
I wish...but they don't need to. It mixes in any quantity. Makes pretty colors!
Wonder how much it'll stain the fairings when a sump starts dripping
Checkout_my_Six
Touchdown! Greaser!
fireside sale?.....they'll prolly just give it away to empty the tanks.
Create a new astm aviation fuel spec? Rather then meeting or modifying existing. Pipe dream
The blue dye in 100ll is a nice safety feature in that it make leaks obvious.
Otoh, maybe another benefit of g100ul is I won't feel so worried about getting my tanks resealed
Checkout_my_Six
Touchdown! Greaser!
George says they have two tank rigs that have been circulating GUL for over a year. No problems.....I have a feeling my 50 yo bladders will need replacing soon.The blue dye in 100ll is a nice safety feature in that it make leaks obvious.
Otoh, maybe another benefit of g100ul is I won't feel so worried about getting my tanks resealed
He also said there were a few "sealed" barrels of the stuff that survived in Florida for a year or so....all should be fine.
In all seriousness....we have more to learn. Standby. But, we'll have to start using it to figure out the rest.
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But did ASTM D910 even exist back when his C-120 was originally certificated?
Doubtful, but there was an existing MIL-SPEC or MIL-STD covering aviation gasoline that was applicable to civilian aircraft with similar requirements. There was a huge change about 30 years ago that dropped MIL specs for civilian specs like ASTM or SAE for most requirements.
I'm expecting that the change over, assuming it happens, will be pretty abrupt when it does. I don't see most FBOs adding another tank and pump nor do I think they'll switch out 100LL for a more expensive fuel that not everyone will have the STC for.
The only way this happens is either by a federal ban or enough small state/municipal ones that it cuts 100LL demand to the point they stop making it. Either way I expect we're at least a few years out.
To be clear I'm not opposed to it, I'm hoping getting the lead gunk out of our engines has some maintenance advantages. However, until that's proven if I have the option of 100LL for $1 less/gallon I'm not eager to jump on that bandwagon.
The only way this happens is either by a federal ban or enough small state/municipal ones that it cuts 100LL demand to the point they stop making it. Either way I expect we're at least a few years out.
To be clear I'm not opposed to it, I'm hoping getting the lead gunk out of our engines has some maintenance advantages. However, until that's proven if I have the option of 100LL for $1 less/gallon I'm not eager to jump on that bandwagon.
That also requires an STC. And around here it's more expensive than 100LL.
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tonycondon
Gastons CRO (Chief Dinner Reservation Officer)
at least 94UL is "aviation gasoline"
Skymac
Pre-takeoff checklist
Yeah... I'm a bit turned off by the STC being locked to engine serial number. That means this is a recurring charge (I do exchange engines over field OH) to get permission to buy the fuel that can't be bought yet. Wat? I've bought some stupid ish before, but that seems like an extra-frivolous torching of $1200.
I read a remark elsewhere that GAMI now has a chicken-and-egg problem with adoption and availability, and that resonates a bit.
For $1200, it is lower risk for me to ask forgiveness instead of permission. "Oops, I didn't see the G at the pump, myyyyy baaaaaaaad"
I think they'd do better to just add 5c to the pump price and not block people from buying their fuel due to a lack of paperwork. I get that they have R&D to recoup. But I also feel like it's an "okay so pick one" situation. Royalty per gallon or STC, but both feels icky. Especially with other contenders. The issue is far from settled, GAMI is just first to the post.
Once 100LL is killed with no viable alternative, though, I'll rub the feet of the statue of St. Braly like everyone else.
I agree, STC is garbage… Give a list of approved engines and add it to the price at the pump.
There's only one airport within 100 miles of me that has 94UL, but it's a dollar cheaper than 100LL. Yes, it requires a STC for you non-experimental types, but it's only $100 for their "forever" STC.
Pinecone
En-Route
G100UL does not meet ASTM D910, so it is not technically aviation gasoline.
So how do you make it legal to use in aircraft where the Type Certificate requires aviation gasoline??????
SkyChaser
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SkyChaser
Have the FAA declare it aviation gasoline? If the gas really is developed for airplanes, it's not like the airplane cares if it's been declared avgas or not. Either the gas is good and works, and the FAA should just admit it's avgas, or it's bad and no one should be using it anyway.
In general, that is not for the FAA or any other CAA to determine. Its the function of the standards provider like ASTM or SAE or the previous MIL-SPEC group. There are a number of AVGAS ASTM standards out there. For example, UL91 and UL94 fall under a ASTM AVGAS standard/spec. It's just not the D910 AVGAS standard that is the internationally accepted one for TC aircraft. Hence the reason for STCs.
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Bro do you even lift
you know who else had an STC like this? do you??? Vilos Cohaagen. that's right.
Great movie! I just can't totally recall the name of it.
John-Paul Townsend
Filing Flight Plan
eman1200: "Open your mind!"
As someone mentioned, the STC sales are part of the effort to fund the deployment of the fuel. Remember, this is all non-taxpayer funded R&D. You think there would be a giant environmental grant for this effort to eliminate lead, but alas, that's not so. It's basically been funded by the sale of GAMI's other products and services. That's right, Virginia, when you buy a set of GAMIjectors a portion of that goes to fund R&D efforts designed to make GA product improvments. As someone else mentioned, there may be a day when the need for an STC goes away. The FAA doesn't currently have a mechanism in place to make that a reality, but our plan is to have our fuel on the market in significant quantities before that happens, if ever.
Jpt
As someone mentioned, the STC sales are part of the effort to fund the deployment of the fuel. Remember, this is all non-taxpayer funded R&D. You think there would be a giant environmental grant for this effort to eliminate lead, but alas, that's not so. It's basically been funded by the sale of GAMI's other products and services. That's right, Virginia, when you buy a set of GAMIjectors a portion of that goes to fund R&D efforts designed to make GA product improvments. As someone else mentioned, there may be a day when the need for an STC goes away. The FAA doesn't currently have a mechanism in place to make that a reality, but our plan is to have our fuel on the market in significant quantities before that happens, if ever.
Jpt
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Bro do you even lift
I don't know where folks are getting this from. "Aviation gasoline", or "Avgas" is not a uniquely defined or trademark term to my knowledge, it loosely describes a class of fuels used in general aviation airplanes. The sticker provided by GAMI says "G100UL Avgas".
John-Paul Townsend
Filing Flight Plan
Correct. By its certification, G100UL is an "aviation gasoline."
Jpt
(edited for a typo)
So if the TC just says "73 octane min aviation gasoline" with no specification...
Question for @John-Paul Townsend ... Would GAMI look at STC sales as a "next up" list? We know California is going to be first. But once it expands, will it be up to airport managers or would you look at an area with more stc holders?
John-Paul Townsend
Filing Flight Plan
The TCDS also says "No. of Seats 2." That doesn't mean that you can take the seats out of your Corvette and put them in your 120. They still have to be the seats that are certified for use in that aircraft. The same is true for fuel, or (almost) any other product.
FYI: it is in certain contexts. The trick is in how to apply that definition. For example, the STC for MOGAS doesn't change its ASTM spec classification from motor gas to aviation gas. The STC merely approves the use of an ASTM motor gas in an aircraft. For another, the EIA defines aviation gasoline specifically to those fuels that meet ASTM Specification D 910 and Military Specification MIL-G-5572. So it depends. Even states have legal definitions of "aviation gasoline" which fall under a different topic all togather.
Sorry to get pedantic, but as I said, it is not a uniquely defined term.
John-Paul Townsend
Filing Flight Plan
"Who's next" is really a logistical problem with multiple variables. For example, once we have rail cars loaded with fuel going to SoCal, stopping in Arizona or extending to Oregon is easier than supplying New York next. However, if all the New England states suddenly ban 100LL, we'll probably start heading there next. It also makes sense to look at airport density and local gallons used. It would make more sense to hit a transfer station centrally located to 5-6 busy airports, than to target a lone airport surrounded by corn fields for 100 miles in any direction. However, if that lone airport was home to a large flight school that used 2 million gallons a year, that might make more sense.
I don't have any "insider knowledge" on this, but I suspect the fuel will travel from Southern Texas to up and down the west coast, then from Texas to Florida and up the east coast, then up through the Midwest. That's all speculation, though. Those details are still being worked out.
Jpt
Dad sold cars for a living. Anytime he had to pump gas, he always wore gloves. Taught me the same, whether the car or the airplane. I haven't read the study but just smelling any fuel convinced me that it shouldn't be on my skin or inhaling it.
FPK1
Line Up and Wait
Sound like they can use some G100UL here!
https://sites.google.com/view/quietskiesoverarapahoecountyco/home?authuser=0&pli=1
https://sites.google.com/view/quietskiesoverarapahoecountyco/home?authuser=0&pli=1
It's odd that there's no mention of G100UL in this:
https://generalaviationnews.com/2023/02/04/bill-introduced-in-washington-state-to-ban-100ll/
https://generalaviationnews.com/2023/02/04/bill-introduced-in-washington-state-to-ban-100ll/
Centennial (KAPA) just announced they'll have 94UL sometime this year. Altho I'm not based there, it's only a 15-20 flight so I guess I should get the STC soon, just in case.
NordicDave
En-Route
Interesting. We have 94UL at many airports from south of San Francisco to just north of Monterey. It cost exactly $1 more per gallon then 100ll. My understanding is 94UL is only refined in the Midwest and must be trucked around the country. Makes it expensive by the time it is out here.
FPK1
Line Up and Wait
I believe the 94UL STC does not cover nearly as many aircraft and engines as the G100UL...
NordicDave
En-Route
You're right, though I believe I read 94UL would work on 75% of the planes in the current fleet. Definitely not 100% but a respectable number.
Of course... there were a lot of aircraft and engines that couldn't run on 80/87, too.
57c is the only place I know that has it. Not far from Swift, although I don't know where Swift has it refined. And it's exactly 1.00 more per gallon. I think it's more scale than freight.